Selecting Gear Size

Workign out the clearances for the gear size it not easy.

My orignal sketch in Tinkercad looked like this:-

But sketching out the motor size and the gear size, identifies a problem.

The clearance is ((gear_size)-(Motor_size))/2 or just two thicknesses of 3mm. Not enough ...

Notes On Installation

Been a while, but I am going to have another bash at this project. With a new type of machine:-

Basically an conveyor belt, for the y-axis, a simple rails system in the style of any inkjet printer for the x-axis and a solenoid for the z-axis ...